////////////////////////////////////////////////////////////////////////////////
// This file is part of the Mist compiler.                                    //
//                                                                            //
// Copyright (C) 2009 The Mist project                                        //
//                                                                            //
// For a list of contributors, see the COMMITTERS file.                       //
//                                                                            //
// The Mist compiler is free software: you can redistribute it and/or modify  //
// it under the terms of the GNU General Public License as published by       //
// the Free Software Foundation, either version 3 of the License, or          //
// (at your option) any later version.                                        //
//                                                                            //
// The Mist compiler is distributed in the hope that it will be useful,       //
// but WITHOUT ANY WARRANTY; without even the implied warranty of             //
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the              //
// GNU General Public License for more details.                               //
//                                                                            //
// You should have received a copy of the GNU General Public License          //
// in the COPYING file. If not, see <http://www.gnu.org/licenses/>.           //
////////////////////////////////////////////////////////////////////////////////

///
/// \file
/// Contains the implementation of the find_references function.
///

#include "findreferences.hpp"

////////////////////////////////////////////////////////////////////////////////
// Includes                                                                   //
////////////////////////////////////////////////////////////////////////////////

#include "common/assert.hpp"
#include "nodes.hpp"
#include "tree.hpp"
#include "navigator.hpp"

////////////////////////////////////////////////////////////////////////////////
// FindReferencesVisitor Class                                                //
////////////////////////////////////////////////////////////////////////////////

/// Visits the nodes of an abstract syntax tree to find the symbols to
/// its references.
///
class FindReferencesVisitor : public Navigator {
	public:
		
		VISIT_FUNCTIONS_FROM( (Reference) )
		
		set<wptr<Symbol> > symbols;
};

////////////////////////////////////////////////////////////////////////////////
// Function Implementations                                                   //
////////////////////////////////////////////////////////////////////////////////

set<wptr<Symbol> > find_references(wptr<Node> tree) {
	assert(tree);
	
	sptr<FindReferencesVisitor> visitor(new FindReferencesVisitor);
	
	tree->accept(visitor);
	
	return visitor->symbols;
}

////////////////////////////////////////////////////////////////////////////////

void FindReferencesVisitor::visit(wptr<Reference> node) {
	assert(node);
	
	symbols.insert(node->symbol());
}
